Cushion spring



June 27, 1933. v c. J. THOMAS CUSHION SPRING Filed July 15, 1951 INVENTOR. CHA LEM THO/m;

AT ORNEY;

4 CHARLES J'. THOMAS, OF LANSDOWNE,

interlocking key such as Patented June 27, 1933 UNITED STATES PATENT OFFICE.

INCL, OE PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF DELAWARE CUSHION SPRING Application filed July 15', 1931. Serial No. 550,820.

This invention relates to cushion springs and more particularly to springs used in mat assemblies to form inner cushion members in mattresses, pillows, and similar cushion elements.

It is among the objects of this invention; to improve the construction 1 of cushion springs; to provide a. series of substantially identical spring elements susceptible to quick and easy assembly; toprovide in cushion spring assemblies an mproved key device for interlocking adjacent springs to form a mat; to provide a cushion spring mat assembly of great flexibility but which is substantially to provide a cushion spring elements and manually attachable interlocking key devices of simple construction and disposed for quick and easy assembly at a'minimum of labor cost, and so arranged that a mat can be extended laterally or transversely to substantially any desired outline or area according to requirements; to

provide a combination of spring units and interlocking keys to preclude weaving of one spring unit relative to another; and many other objects and more apparent as'the description proceeds.-

In the accompanying drawing Fig. 1 represents'a fragmentary plan of a cushion spring interlocked mat assembly according to'this invention, disclosing at the lower right hand corner a modified form of is contemplated in the invention,

Fig. 2 represents a vertical section through the interlocking elements of adjacent units in the mat assembly as taken on line 2-2 of Fig. 1,

Fig. 3 represents a transverse vertical section through the interlocking elements of adj acent units in the mat assembly as taken on line 33 of Fig. 1,

Fig. 4 represents a fragmentary elevation of the interlocking elements of a pair of as semb-led spring units,

I Fig. 5 represents a plan of a preferred form of interlocking key, and

Fig. 6 represents a modified form of interlocking key.

advantages, as will become p It is customary in effecting the so called inner spring mattresses and the like, to prov de a series of coil springs in juxtaposit1on with their respective upper and lower faces or end turns of wire in common planes and with their axes in parallelism and to provide mechanical fastening devices engaging contiguous parts of adjacent springs to form them into mats. The fastening devices are usually metallic clips or the. like, which are mechanically, or, with the suitable tools, manually clamped or otherwise secured about adacent portions of end turns of the wire of the springs. In most cases such fastening elements sharply diminish the flexibility o'f the mats and contribute to the noise factor incident to flexing of the mats.

PENNSYLVANIA, ASSIGNOR '10 KIWI MFG. 00., I

In the invention disclosed herein each coil spring 10, which may be of any desired type, has a substantially identical end turn 11 at bothltop and bottom, which turn carries a plurality, preferably four, of locking lugs 12. The locking lugs are preferably diametrically oppositely disposed upon the'respective' end turns 11 and, being identical,'need be described in detail but once. For this urpose consider the righthand lu'g of Fig. 1, in which the end turn llhas a bend'13, an outwardly directed leg 14, a base element 15 merges into leglt in an acute angle at 16. Base 15 terminates in an acute angle 17 and merges into an inwardly minating in a shoulder 20 which merges with 'theremainder of'end" turn 11. I In the purely illustrative disclosure a slight space is provided between knuckles 18 and 20, although this space may be larger or smaller than shown according to requirements. It will be observed that the triangular locking lug 12 as described has a base which is substantially tangential to the end turn 11, or is parallel to such tangent. As shown the locking lug 12 may lie in'the common plane containing end turn 11 or it'may be bent upwardly or downwardly out of such plane so that the base 15 is either above or below such plane, as desired.

The instant invention does not deal with or relate tosuch interlocking factors as may attach to and maintain between the locking directed leg 18, ter 7 rod lugs themselves, but contemplates the provision of a separate and independent interlocking key which may be and preferably is man ually associated with a pair of locking lugs.

-Referring to Fig. 5, for instance, there is as defined by the inn-er surfaces of the curved connections 16 and 17, is a similar elongated hole 24 having a slot 25 leading to the edge of the sheetof material.

It may be noted that the key disclosed in Fig. 5 provides the opening 23 with shoulders or tabs 26 and 27 formed on opposite sides of slot 22 while slot on the other side of the key defines with an elongated opening 24, shoulders 28 and 30. These tabs or shoulders have a locking function which is of importanee.

The particular material which may be best adapted for the purposes of the key may well vary according to requirements but it is de sir-able that the key have a certain flexibility or resilience, that it have strength, and preferably long life. Under certain conditions I have found leather to be a very desirable locking key as it has in addition to the factors of easy workability and manipulatability a sound damping and vibration absorbing quality. For general purposes, however, vulcanized fibre answers most of the requirements, including the factor of economy and low cost. Under certain conditions it might be possible to use sheet metal or even a key made of wire. It is contemplated that certain woven materials might be utilized, such as a heavy duck or canvas, either alone or in association with an impregnation of a stiffening material such as rubber or a phenolic condensation product.

It will be understood that the flexibility of the key 21 is such that the operator may hold a spring in one hand and move the key in the other hand to a position perpendicular to the plane of the end turn of the wire coil, and by moving the key between the shoulders 13 and 20 may cause the slot 22 to open far enough to slide upon base 15 until the curved connection 17 is received in the opening 23. Manipulation of the key there after and the distortion of the locking lug if necessary (it being of such resilience as to permit such distortion), enables the operator then to move the key into such position that the slot 25 may open to receive the other end of the base 15, until the curved connection 16 is received in the elongated hole 24. The parts will then be in the position indicated by one-half of the several locking keys shown in Fig. 1. Similarly by manipulating the respective springs bodily and by flexing desired portions thereof as well as by flexing the key, the operator is enabled to cause a similar engagement of the adjacent locking lug by the key as to a position as shown in Fig. 1. In such locked relation it will be observed that the base elements of each looking lug will be disposed in parallelism in abutting engagement as the slots or holes 23 and 24 are so shaped and of such size as to receive the base members simultaneously, while the respective tabs, tongues, or shoulders 26, 27, 28 and 30 will be below the level of the base members to prevent undesired movement thereof, while the relationship of the locking lugs to the remainder of the keys is such as substantially to preclude movement of one locking lug relative to another in the same key. The lock is such that although a hinge action is permitted as in the normal flexing of the springs in the use of the assembled mats, yet movement of one spring relative to another in such manner as would tend to move the base locking lugsout of parallelism is precluded. Although it might be possible in certain instances to secure un locking relation of a key and a single pair of 7 locking lugs, yet this must be done deliberately and not as a concomitant of normal use. Moreover when a given spring unithas been locked on aplurality of sides to adjacent'springs a positive anchored engage-j ment is had which is only broken by positive manual manipulations.

The modified form of key disclosed in F ig. 6 is particularly designed to secure. all

of the benefits'of the close interlocking association of the key shown in Fig. 5, with the: advantage. of wider spacing of the spring,

units without-sacrifice of the substantial integrality of the whole. Inthisform smaller holes or apertures as 31 and 32, are provided at one end and independent apertures or holes 33 and 34, are provided toward the other end. It facilitates the interlocking of the larger key ifthe slots through which the wires pass to enter the apertures 31 and 32,

and 33 and 34, respectively, merge into the respective apertures at a tangent thereto rather than diametrically thereof. The slots for identification are numbered 35 to 38 respectively, and the modified key'as a whole may be identified as 40, and having tabs, tongues or shoulders formed by the slots 35, 36, '37 and38, by characters 41 to 48 in clusive.

It will be clear that in place of end turns 1.1, the turn carrying the locking lugs mightbe formed between the end turns ofa given spring unit.

I claim as my invention:

1; As an article of manufacture arranged for removable association with a pair of juxtaposed triangular'locking lugs of independent spring elements, a sheet of material.

tive apertures to the edges of the key and arranged to receive the bases of both lugs, shoulders being formed on the key laterally of the apertures adjacent the respective slits and arranged to engage an edge of the respective bases of the locking lugs.

3. Ina cushion spring assembly a pair of spring units having each an open triangular locking lug the bases of which are parallel with a tangent to the adjacent portion of the spring element, the springs so disposedv that the bases of the lugs are in substantial parallelism and in substantial abutment, flexible means comprising a single sheet of material attached to the respective lugs and having spaced apertures each of which is arranged to receive the bases of both lugs including a portion imposed upon the abutting bases, and shoulders mounted on the flexible means and engaging beneath the legs of the respective lugs and slits extending from the respective apertures to the respective edges of the flexible means to facilitate manual attachment of the flexible means to the locking lugs.

4. In a cushion spring mat assembly, a spring unit, a substantially triangular looking lug on said unit comprising a base and angularly disposed legs, a locking key having means on one side engaging within the lug where the base and a leg merge, an aperturejformed on the key and spaced from the first means by substantially the length of the base of the lug, shoulders formed by the aperture, a slit extending from the aperture to an edge of the key in parallelism with the base of the lug and forming access to the aperture shoulders to engage the other leg of the lug, said key arranged to engage a similar locking lug on an adjacent spring of the assembly to flexibly connect adjacent spring units.

Signed at Philadelphia, county of Philadelphia, and State of Pennsylvania, this 14th day of July, 1931.

CHARLES J. THOMAS. 

